1. Field of Invention
The present invention relates to a novel method for treatment of angina pectoris. A .beta.-adrenergic-blocking agent is administered acutely to a patient having angina. The dose is desirably provided by nasal administration to provide an essentially immediate, therapeutically effective amount of blocking agent to treat the angina.
2. Description of the Prior Art
Angina occurs when cardiac work and myocardial oxygen demand exceed the ability of the coronary arteries to supply oxygenated blood. The myocardium becomes ischemic and, accompanied by myriad physiological and chemical changes, symptoms such as pain result.
The discomfort of angina pectoris is most commonly felt beneath the sternum. It may range from a vague ache to an intense precordial crushing sensation. It may also radiate, usually to the left shoulder and arm, but also through the back, into the throat, jaws and/or teeth and elsewhere. Anginal discomfort may even be felt in the upper or lower abdomen.
Angina is characteristically triggered by physical exercise. The response to exercise is usually predictable but, in some patients, a given stress may be tolerated one day and precipitate angina the next. Attacks vary in frequency, being separated by symptom-free intervals of as long as weeks, months, and even years. They may also increase to a fatal outcome.
.beta.-adrenergic-blocking agents are well known for the prophylaxis of angina. However, these blocking agents have not generally been shown to be effective for acute uses such as the management of an angina attack. Once an attack has commenced, the treatment of choice is normally nitroglycerin.
As a result of the foregoing, a normal procedure for individuals subject to angina involves the daily administration of a prophylactic dosage of a .beta.-adrenergic-blocking agent such as propranolol. This essentially involves maintaining a therapeutic level or concentration of blocking agent in a person's bloodstream on a long term basis which may be indefinite in duration.
That procedure has been shown to be effective in reducing the frequency of angina attacks in humans. A drawback, however, is the requirement for virtually constant drug therapy. Various adverse reactions to .beta.-adrenergic-blocking agents are known. In particular, at the high level of dosage utilized for prophylaxis, there are possibilities of side effects such as bradycardia, hypotension and dizziness. Further, abrupt discontinuance of the drug has still other potential effects including the precipitation or exacerbation of angina, myocardial infarction and ventricular dysrhythmias.
Another drawback of that procedure involves individuals having certain complications. For example, those who are pregnant, suffering hepatic impairment or having bronchitis or emphysema can be subjected to its long term, virtually constant drug exposure only under closely monitored conditions, if at all. Consequently, many prospective patients are precluded from the benefits of that procedure.